Suppression of amber and ochre rII Mutants of Bacteriophage T4 by Streptomycin

Orias, E. (University of California, Santa Barbara), and T. K. Gartner. Suppression of amber and ochre r II mutants of bacteriophage T4 by streptomycin. J. Bacteriol. 91: 2210–2215. 1966.—Streptomycin-induced suppression of amber and ochre r II mutants of phage T4 was studied in a streptomycin-sensitive strain of Escherichia coli and four nearly isogenic streptomycin-resistant derivatives of this strain, in the presence and in the absence of an ochre suppressor. Most of the 12 r II mutants tested were suppressed by streptomycin in the streptomycin-sensitive su − strain. This streptomycin-induced suppression in the su − strain was eliminated by the independent action of at least two of the four nonidentical mutations to streptomycin resistance. In two of the su + str-r strains, streptomycin markedly augmented the suppression caused by the ochre suppressor. In those su − str-r hosts in which significant streptomycin-induced suppression could be measured, the amber mutants were more suppressible than the ochre mutants.